Pyrotinib Combined With Brain Radiotherapy in Breast Cancer Patients With Brain Metastases

Brain metastases occur in 30-50% of patients with metastatic HER2-positive breast cancer. Pyrotinib is an irreversible pan-ErbB receptor tyrosine kinase inhibitor (TKI) with activity against epidermal growth factor receptor (EGFR)/HER1, HER2, and HER4. This study consists of two parts. In a phase Ib part, investigators will explore the safety and tolerance of Pyrotinib Plus Capecitabine combined with brain radiotherapy. After completing the phase Ib part, investigators will review the data and decide whether this patient is included in before the start of a phase II part. In the phase II part, investigators will evaluate the efficacy of Pyrotinib Plus Capecitabine combined with brain radiotherapy in patients with HER2 positive breast cancer patients with brain metastases.